The Incentives and Effectiveness of Vote Buying : A Comparison of SNTV and FPTP Voting Systems

We examine the effect of electoral system on vote-buying incentives and the effectiveness of vote buying. We find that under SNTV greater numbers of candidates in a district, larger district magnitude, or higher effective threshold are all associated with prevalent vote-buying practices. In those districts, candidates face intense intra-party competition and only needs to gather a small portion of votes to be elected, both factors contributing to widespread vote buying. In contrast, under FPTP the number of candidates in a given district and effective threshold are no longer significant predictors of vote buying. As for the effectiveness of vote-buying, we find that under SNTV voting system vote-buying is positive and significant, showing that candidates who buy votes enjoy a greater probability of being elected. On the other hand, past vote-buying records do not affect electoral performances. In contrast, under FPTP vote-buying is no longer a significant factor affecting winning or losing, while past voting records are negatively associated with the elected probabilities